Pre Start-Up Checks

1.Check all fasteners for tightness. The wheel should rotate freely and not rub on the fan panel venturi. Turn the fan on momentarily to check for unusual vibration or noise. Do not run the fan more than a few seconds without being connected to the system for which it was designed. Motor overloading and burnout may result from lack of system static pressure.

2.Inlet and discharge collars are provided for duct connection. The inlet panel is removable for attaching optional filter box accessory.

3.Wheel Rotation: Direction of wheel rotation is critical. Check wheel rotation by momentarily energizing the unit. Improper rotation will result in reduced airflow and pressure capabilities.

Rotation is always in the same direction as airflow at the outlet. See housing and wheel examples in figure 4.

ATIO N

T

RO

AIRFLOW

TIO N

 

 

 

 

A

 

 

T

 

 

O

 

 

R

 

AIRFLOW

 

 

 

 

 

 

 

 

Figure 4:

Wheel Rotation Guide

CORRECTWRONG

WARNING

Correct direction of wheel rotation is critical. Reversed rotation will result in poor air performance, motor overloading and possible burnout.

4.Vibration Isolators: After fan is moved to

desired location, punch out the four knock-out holes which are located on the unit top and bottom panels. Assemble the brackets to the unit according to the appropriate drawings on page 3 and refer to respective parts list on page 7. Make certain all connectors are tight and that all washers are in.

5If adjustments are made, it is very important to check the pulleys for proper alignment. Misaligned pulleys lead to excessive belt wear, vibration, noise and power loss. (See figure 5)

6.For all BDF Fans: Belt tension can be adjusted by loosening four fasteners (marked “R”, figure 6) on the drive frame. The motor plate slides on the slotted adjusting arms (see figure 17). Belt tension should be adjusted to allow 1/64 inch of deflection per inch of belt span.

For example, a 15 inch belt span should have 15/64 inch (or about 1/4 inch) of deflection with moderate thumb pressure at mid-point between pulleys (See figure 7). Overtightening will cause excessive bearing wear and noise. Too little tension will cause slippage at startup and uneven wear.

R

NOTE:

Identical fasteners on opposing side must also be loosened.

Figure 6

WRONGWRONG

Deflection =

Belt Span

Belt Span

 

64

 

 

Figure 7

Figure 5

4

Model BDF • Belt Drive Duct Fan

®

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Image 4
Greenheck Fan BDF manual Pre Start-Up Checks, Vibration Isolators After fan is moved to